WAVE CONDUCTORS FOR TRANSMISSION OF ELECTROMAGNETIC WAVE SIGNALS

Description

FIELD OF THE INVENTION

[0001] The present invention relates to a waveguide for transmission of electromagnetic wave signals.BACKGROUND

[0002] As data traffic is rapidly increased, data transmission / receipt speed of I / O bus connecting integrated circuits is also being quickly increased. For last decades, conductor-based interconnects (e.g., copper wires) with high cost and power efficiencies have been widely applied to wired communication systems. However, such conductor-based interconnects have inherent limitations in channel bandwidths due to skin effect caused by electromagnetic induction.

[0003] Meanwhile, optic-based interconnects with high data transmission / reception speed have been introduced and widely used as an alternative to the conductor-based interconnects. However, the optic-based interconnects have limitations in that they cannot completely replace the conductor-based interconnects because the costs of installation and maintenance thereof are very high.

[0004] Recently, a new type of interconnect comprising a waveguide composed of dielectric has been introduced. Since the new type of interconnect (so-called e-tube) has advantages of both of metal and dielectric, it has high cost and power efficiencies and enables high-speed data communication within a short range. Thus, it has come into the spotlight as an interconnect employable in chip-to-chip communication.

[0005] For example, US 2015 / 295300 A1 discloses waveguides with dielectric cores surrounded by a cladding along the length of the DWG.

[0006] In US 2014 / 368301 A1 shielding of dielectric waveguides is described wherein a dielectric cladding surrounds the dielectric core member and a conductive shield layer surrounds a portion of the dielectric cladding.

[0007] In US 2018 / 097268 A1 A method of making a waveguide ribbon wherein the method comprises joining a first sheet of dielectric material to a first conductive sheet of conductive material, patterning the first sheet of dielectric material to form a plurality of dielectric waveguide cores on the first conductive sheet, and coating the dielectric waveguide cores with substantially the same conductive material as the conductive sheet to form the plurality of waveguides.

[0008] An article in BIOMEDICAL PHOTONICS AND OPTOELECTRONIC IMAGING of Nov. 2000 discloses a hollow-core waveguide with sub-wavelength scale metallic wires in the cladding for THz guidance.

[0009] US 2007 / 188261 A1 also discloses waveguides with dielectric cores partially surrounded by conductive cladding.

[0010] However, even when a conventional dielectric waveguide is used, there is a problem that a great change or variation in a group delay is caused by a non-linear phase response, or that bit errors are caused by increasing a data transfer rate (or bandwidth).

[0011] In this regard, the inventor(s) present a technique for a novel and inventive waveguide that can mitigate non-linearity of phase responses and prevent bit errors from occurring in a high-speed data communication environment.SUMMARY OF THE INVENTION

[0012] One object of the present invention is to solve all the above-described problems.

[0013] Another object of the invention is to provide a waveguide comprising a first dielectric part, a conductor part, and a second dielectric part, wherein the conductor part covers a part of the first dielectric part and the second dielectric part surrounds all of the first dielectric part and the conductor part, so that both of dielectric-conductor boundary conditions and dielectric-dielectric boundary conditions exist as boundary conditions applied to a signal transmitted through the waveguide.

[0014] According to the present invention, a waveguide is provided as set forth in claim 1. Preferred embodiments are set forth in dependent claims. The representative configurations of the invention to achieve the above objects are described below.

[0015] An object of the invention is to provide a waveguide for transmission of electromagnetic wave signals, comprising: a first dielectric part comprising a dielectric; a conductor part covering a part of the first dielectric part; and a second dielectric part surrounding the first dielectric part and the conductor part, wherein the conductor part surrounds a part of the first dielectric part, and the second dielectric part surrounds all of the first dielectric part and the conductor part, wherein the first dielectric part is in the form of a rectangular core and the conductor part is in the form of a cladding covering upper and lower surfaces of the first dielectric part, and the second dielectric part is in the form of a rectangular jacket and surrounds all of the first dielectric part and the conductor part as seen from a cross-section cut along a direction perpendicular to the length of the waveguide and wherein the waveguide is configured such that a signal transmitted through the waveguide is guided along a boundary between the first dielectric part and the conductor part, and a boundary between the first dielectric part and the second dielectric part.

[0016] In addition, there are further provided other waveguides to implement the invention.

[0017] According to the invention, both of dielectric-conductor boundary conditions and dielectric-dielectric boundary conditions may exist as boundary conditions applied to a signal transmitted through a waveguide, so that linearity of phase responses occurring in the signal transmitted through the waveguide may be increased.

[0018] According to the invention, it is possible to mitigate non-linearity of phase responses in communication using a waveguide, so that the degree of change in a group delay according to a frequency change may be reduced.

[0019] According to the invention, it is possible to make a non-dispersive signal transmission channel via a waveguide, so that intersymbol interference (ISI) may be reduced and the frequency with which bit errors occur as a data transfer rate is increased may be drastically reduced.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 illustratively shows the configuration of a waveguide according to prior art. FIG. 2 illustratively shows the configuration of a waveguide according to the invention. FIG. 3A illustratively shows the configuration of a waveguide according to another embodiment of the invention. FIG. 3B illustratively shows the configuration of a waveguide according to an example not forming part of the claimed invention but being nonetheless useful for the understanding of the invention. FIGS. 4 and 5 show how to estimate a group delay that may occur in a waveguide according to prior art, and a group delay that may occur in a waveguide according to one embodiment of the invention. FIGS. 6A and 6B show results of tests in which a group delay is measured for each of the cases where signals are transmitted / received using a waveguide according to the invention and using a waveguide according to prior art. FIGS. 7A and 7B illustratively show the configurations of waveguides according to yet another embodiment of the invention. DETAILED DESCRIPTION

[0021] In the following detailed description of the present invention, references are made to the accompanying drawings that show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It is to be understood that the various embodiments of the invention, although different from each other, are not necessarily mutually exclusive. For example, specific shapes, structures and characteristics described herein may be implemented as modified from one embodiment to another without departing from the scope of the invention. Furthermore, it shall be understood that the locations or arrangements of individual elements within each of the disclosed embodiments may also be modified without departing from the scope of the invention. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of the invention, if properly described, is limited only by the appended claims.

[0022] In the drawings, like reference numerals refer to the same or similar functions throughout the several views.

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings to enable those skilled in the art to easily implement the invention.Configuration of the waveguide

[0024] Hereinafter, the internal configuration of a waveguide crucial for implementing the present invention and the functions of the respective components thereof will be discussed.

[0025] FIG. 1 illustratively shows the configuration of a waveguide according to prior art.

[0026] Referring to FIG. 1, the waveguide according to prior art may comprise a dielectric core 11 and a conductor cladding 12 surrounding the dielectric core 11.

[0027] When signals are transmitted using the waveguide according to prior art, there may arise problems that a great change or variation in a group delay is caused by a non-linear phase response, and that the frequency with which bit errors occur is increased as a data transfer rate is increased in an actual communication environment.

[0028] FIG. 2 illustratively shows the configuration of a waveguide according to the invention.

[0029] Referring to FIG. 2, a waveguide 100 according to the invention comprises a first dielectric part 110 comprising a dielectric; a conductor part 120 covering a part of the first dielectric part 110; and a second dielectric part 130 surrounding the first dielectric part 110 and the conductor part 120. Here, according to one embodiment of the invention, the dielectrics included in the first dielectric part 110 and the second dielectric part 130 may have different permittivity.

[0030] Specifically, according to one embodiment of the invention, the conductor part 120 may be formed to cover some of a plurality of outer surfaces of the first dielectric part 110.

[0031] More specifically, according to one embodiment of the invention, the central axes of the first dielectric part 110, the conductor part 120 and the second dielectric part 130 may coincide with each other.

[0032] For example, as shown in FIG. 2, the first dielectric part 110 is in the form of a rectangular core and the conductor part 120 is in the form of a cladding covering two of four surfaces (i.e., upper and lower surfaces) of the first dielectric part 110 in the form of the rectangular core, while the second dielectric part 130 may be in the form of a rectangular jacket surrounding all of the first dielectric part 110 and the conductor part 120, as seen from a cross-section cut along a direction perpendicular to the length of the waveguide 100 according to one embodiment of the invention.

[0033] However, it is noted that the internal configuration or shape of the waveguide 100 according to the invention is not necessarily limited to those mentioned above, and may be changed without limitation as long as the objects of the invention can be achieved.

[0034] FIGS. 3A and 3B illustratively show the configurations of waveguides according to another embodiment of the invention.

[0035] First, referring to FIG. 3A, in the case of a waveguide 200 according to another embodiment of the invention, a first dielectric part 210 may be in the form of a rectangular core and a conductor part 220 may be in the form of a cladding covering three of four surfaces (i.e., upper, lower and left surfaces) of the first dielectric part 210 in the form of the rectangular core, while a second dielectric part 230 may be in the form of a rectangular jacket surrounding all of the first dielectric part 210 and the conductor part 220.

[0036] Next, referring to FIG. 3B, in the case of a waveguide 300 according to an example not forming part of the claimed invention but nonetheless useful for the understanding of the invention, a first dielectric part 310 may be in the form of a circular core and a conductor part 320 may be in the form of a cladding covering a part of an outer surface (corresponding to predetermined angles about the central axis) of the first dielectric part 310 in the form of the circular core, while a second dielectric part 330 may be in the form of an annular jacket surrounding all of the first dielectric part 310 and the conductor part 320.

[0037] Meanwhile, according to yet another embodiment of the invention, it may be assumed that a plurality of waveguides are included in a single cable. Even in this case, the waveguides may be formed such that both of dielectric-dielectric boundary conditions and dielectric-conductor boundary conditions exist.

[0038] FIGS. 7A and 7B illustratively show the configurations of waveguides according to yet another embodiment of the invention.

[0039] First, referring to FIG. 7A, in the case of a waveguide 700 according to yet another embodiment of the invention, a first dielectric part 710 may be in the form of a rectangular core and a conductor part 720 may be in the form of a cladding covering three of four surfaces (i.e., upper, lower and left surfaces) of the first dielectric part 710 in the form of the rectangular core, while two waveguide units each comprising the first dielectric part 710 and the conductor part 720 may be disposed adjacent to each other, and a second dielectric part 730 may be in the form of a rectangular jacket surrounding all of the two waveguide units each comprising the first dielectric part 710 and the conductor part 720.

[0040] Next, referring to FIG. 7B, in the case of a waveguide 800 according to yet another embodiment of the invention, a first dielectric part 810 may be in the form of a rectangular core and a conductor part 820 may be in the form of a cladding covering three of four surfaces (i.e., upper, lower and left surfaces) of the first dielectric part 810 in the form of the rectangular core, while a plurality of waveguide units each comprising the first dielectric part 810 and the conductor part 820 may be disposed in a predetermined arrangement, and a second dielectric part 830 may be in the form of a rectangular jacket surrounding all of the plurality of waveguide units each comprising the first dielectric part 810 and the conductor part 820.

[0041] That is, as shown in FIGS. 7A and 7B, in the case of the waveguides according to yet another embodiment of the invention, even when a plurality of waveguide units are included in a single cable jacket, dielectric-dielectric boundary conditions and dielectric-conductor boundary conditions may exist in each of the plurality of waveguide units.

[0042] Meanwhile, according to one embodiment of the invention, the conductor part 120 may consist of a material having electrical conductivity. For example, the conductor part 120 according to one embodiment of the invention may consist of a metallic material such as copper (Cu) which is traditionally in wide use, or may consist of a non-metallic material such as graphene.

[0043] Meanwhile, according to one embodiment of the invention, the permittivity of the first dielectric part 110 may be greater or less than that of the second dielectric part 130. For example, the first dielectric part 110 may consist of teflon having a dielectric constant of about 2.0, and the second dielectric part 130 may consist of polyethylene having a dielectric constant of about 1.2. Further, as another example, the first dielectric part 110 may consist of air having a dielectric constant of about 1.0, and the second dielectric part 130 may consist of teflon having a dielectric constant of about 2.0. Conversely, the first dielectric part 110 may consist of teflon and the second dielectric part 130 may consist of air.

[0044] Therefore, according to one embodiment of the invention, a signal transmitted through the waveguide 100 (i.e., an electromagnetic wave) may be guided not only along a boundary between the first dielectric part 110 and the conductor part 120, but also along a boundary between the first dielectric part 110 and the second dielectric part 130 having different permittivity. That is, since both of dielectric-conductor boundary conditions and dielectric-dielectric boundary conditions may exist in the case of the waveguide 100 according to one embodiment of the invention, linearity of phase responses occurring in a signal transmission channel via the waveguide may be drastically increased, and thus the degree to which a group delay is changed (or dispersed) according to a frequency change may be drastically reduced. Further, since a non-dispersive signal transmission channel may be made in the case of the waveguide 100 according to one embodiment of the invention, intersymbol interference (ISI) may be reduced and no bit errors may occur even when a data transfer rate is increased. The group delay will be discussed in detail below.

[0045] FIGS. 4 and 5 show how to estimate a group delay that may occur in a waveguide according to prior art, and a group delay that may occur in a waveguide according to one embodiment of the invention.

[0046] First, referring to FIG. 4, in the case of the waveguide according to prior art (i.e., the waveguide comprising the dielectric core 11 and the conductor cladding 12 surrounding all of the dielectric core 11), it may be estimated that the group delay is affected by a change in a frequency ω (i.e., the group delay is changed as the frequency is changed).

[0047] Next, referring to FIG. 5, in the case of the waveguide according to one embodiment of the invention (i.e., the waveguide comprising the first dielectric part 110, the conductor part 120 covering a part of the first dielectric part 110, and the second dielectric part 130 surrounding all of the first dielectric part 110 and the conductor part 120), it may be assumed that the group delay is not affected by a change in a frequency ω (i.e., the group delay is almost unchanged even when the frequency is changed).

[0048] FIGS. 6A and 6B show results of tests in which a group delay is measured for each of the cases where signals are transmitted / received using a waveguide according to the invention and using a waveguide according to prior art.

[0049] First, referring to a S21 graph shown in FIG. 6A, it can be seen that upper corner frequencies or upper cutoff frequencies are substantially the same in a test result 610 for the waveguide according to one embodiment of the invention (i.e., the waveguide comprising the first dielectric part 110, the conductor part 120 covering a part of the first dielectric part 110, and the second dielectric part 130 surrounding all of the first dielectric part 110 and the conductor part 120) (more specifically, the waveguide having a structure as shown in FIG. 3A) and a test result 620 for the waveguide according to prior art (i.e., the waveguide comprising the dielectric core 11 and the conductor cladding 12 surrounding all of the dielectric core 11).

[0050] Next, referring to a group delay graph shown in FIG. 6B, when the waveguide according to prior art is employed, non-linear phase responses may occur, which may increase the degree of change in a group delay according to a change in a frequency in a signal transmission channel via the waveguide. Actually, referring to FIG. 6B, in a test result 620 for the waveguide according to prior art, it can be seen that the degree to which the group delay is changed as the frequency is changed in the frequency band in the graph is relatively large.

[0051] Referring further to the group delay graph shown in FIG. 6B, when the waveguide according to the invention is employed, non-linearity of phase responses may be reduced, which may drastically reduce the degree of change in a group delay according to a change in a frequency in a signal transmission channel via the waveguide. Actually, referring to FIG. 6B, in a test result 610 for the waveguide according to the invention, it can be seen that the degree to which the group delay is changed as the frequency is changed in the frequency band in the graph is significantly small.

[0052] Therefore, from the above test results, it can be seen that when the waveguide 100 according to the invention is employed, the change (or variation) in the group delay of a transmission signal, which may occur as the frequency is changed, may be drastically reduced.

[0053] Although details or parameters for the components included in the waveguide according to the invention have been described above in detail, it is noted that the configuration of the waveguide according to the invention is not necessarily limited to those mentioned above.

[0054] Although the present invention has been described in terms of specific items such as detailed elements as well as the limited embodiments and the drawings, they are only provided to help more general understanding of the invention, and the present invention is not limited to the above embodiments. It will be appreciated by those skilled in the art to which the present invention pertains that various modifications and changes may be made from the above description.

Claims

1. A waveguide (100) for transmission of electromagnetic wave signals, comprising: a first dielectric part (110) comprising a dielectric; a conductor part (120) covering a part of the first dielectric part (110); and a second dielectric part (130) surrounding the first dielectric part (110) and the conductor part (120), wherein the conductor part (120) surrounds a part of the first dielectric part (110, 210, 310, 710, 810), and the second dielectric part (130) surrounds all of the first dielectric part (110) and the conductor part (120), wherein the first dielectric part (110) is in the form of a rectangular core and the conductor part (120) is in the form of a cladding covering upper and lower surfaces of the first dielectric part (110), and the second dielectric part (130) is in the form of a rectangular jacket and surrounds all of the first dielectric part (110) and the conductor part (120) as seen from a cross-section cut along a direction perpendicular to the length of the waveguide (100), and wherein the waveguide (100) is configured such that a signal transmitted through the waveguide is guided along a boundary between the first dielectric part (110) and the conductor part (120), and a boundary between the first dielectric part (110) and the second dielectric part (130).

2. The waveguide of Claim 1, wherein central axes of the first dielectric part (110), the conductor part (120) and the second dielectric part (130) coincide with each other.

3. The waveguide of Claim 1, wherein the dielectrics included in the first dielectric part (110) and the second dielectric part (130) have different permittivity.

4. The waveguide of Claim 1, wherein the waveguide (100) is configured such that a change in a group delay which occurs according to a frequency change in a signal transmission channel via the waveguide (100), does not exceed a predetermined level.